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Old 03-07-2017, 12:23 AM   #16
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Originally Posted by nitrodude View Post
wheel-spin, your problem is lack of grip
Agreed, & if his street is anything like mine, it has a sizable crest to it(in the middle), it's VERY hard to keep a car going straight on it, but would not be an indication of a problem with the car. When I do a break-in or test run in my street, I always have to go carefully, & have to make a LOT of steering corrections, just to keep it in the middle of the street. I wouldn't worry much about whether it's tweaked or not, until you can get the car to a flat surface(like a race track)....
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Old 03-07-2017, 12:25 AM   #17
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No the cars steering wanders on and off power in different directions, all my other cars work fine in the same conditions, yeah I thought it might have been the crown in the middle of the street too.
Trust me, I'm 90% sure that it IS the crown of the street. A 419 is a VERY sensitive car(like all major league touring chassis), you NEED a flat surface to really determine if anything is wrong...
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Old 03-07-2017, 02:58 AM   #18
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My money sez you have unequal toe on the front (possibly on the back as well, TRF cars have had this problem confirmed by many of us in the threads here). That and unequal play means your wheels are not pointing in the same direction on power and off power. I would say if you run a test on a flat surface on and off power you will notice the car changes direction when you back off the throttle.

Difficult to pinpoint without a set up board and even more difficult to correct.

Not to say other things can't contribute, but none of those explains the symptom more readily. Ultimately you can end up (adjusting things without a setup board) to a car that is driving sideways (crabbing). That is the best proof you have unequal toe.

Seized bearings are the closest problem that would create such a symptom and with the same sort of "reliability", but in that case, the car drifts to the same side on or off power, forward or reverse. This is not the case with your car if i udnerstand your description of the symptoms correctly.
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Old 03-07-2017, 03:30 AM   #19
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i drive a xray, i need a lot of flex to be less aggressive.
when i fix the upperdeck to the motormount the car becomes very twitchy.
try get more flex in the rear, also laydown your shocks in the rear.

also weightransfer and balance is important, try to put more weight in the front
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Old 03-07-2017, 12:04 PM   #20
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Tried all your advise, and it still is wandering, on throttle to the right or left, on throttle to the right or left, it does what it wants. and it's not the road I ran my EVO 6 out there and it's fine, even made sure the belts are true and in the middle. Someone please help!!!
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Old 03-07-2017, 12:16 PM   #21
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Worst case scenario, if you dont have a setup board grab a picture frame off your wall and carefully take the glass out. Should just be about slightly bigger than your car, then you can put it on your work table and place your chassis on it - remove the shocks. Then you can see and check for airgaps. Just crude, but close to flat, and gives you a good feeler.

best of luck figuring out your chassis woes.

Also post some pics, the guys running the TRF may spot something.

Given you are running a race chassis on the street, consider its not designed for those conditions.

So, although you have went through the car, best bet, take it all apart and inspect everything - use the glass plate to check for out of round parts, measure parts etc. Reassemble as per instructions, check for tweak as you go.

I highly suggest you watch Gilles videos as they relate to TC, and might be able to get some good tips:

https://www.youtube.com/watch?v=sliCxsIZ3v4

- on another note TRF Guys, not being familiar with the TRF cars, but rac 1/8 IC 4wd, is it possible to have an over or underdrive that would manifest itself this way, given its a pulley car??? just thinking outside the box here.
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Old 03-07-2017, 12:29 PM   #22
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tweak... google it.
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Old 03-07-2017, 12:30 PM   #23
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Originally Posted by 1/8 IC Fan View Post

- on another note TRF Guys, not being familiar with the TRF cars, but rac 1/8 IC 4wd, is it possible to have an over or underdrive that would manifest itself this way, given its a pulley car??? just thinking outside the box here.
no over-under-gearing in 10th DTM EP
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Old 03-07-2017, 12:49 PM   #24
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Make sure you front C hubs are not on backwards. They are marked with an R and and L. R is right side from the drivers perspective. Also when looking at them from the side with the wheel off, there should be. A reward angle to them. Finallay check to make sure they are the same angle. They make 2, 4, and 6 degree hubs thy fit the 419.
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Old 03-07-2017, 12:55 PM   #25
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Since the only thing that touches the ground is the tires, it is always a good idea to make sure they are all in good order. Make sure that they are all glued properly. A tire that has even become partially unglued from the wheel can cause strange handling.

Since the OP mentioned trying a different chassis with success, you might also try to tires from the "good" car on the "bad" car and see if that makes any difference.

----------

As far as over or under gearing, I think what 1/8 IC Fan was saying to check if the car had different size/teeth on the plastic gears on the outside of the diffs (when comparing the front to the back). This is certainly a tuning option that is available on many 1/10 belt drive touring cars.
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Old 03-07-2017, 01:29 PM   #26
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Wandering in various directions is probably the servo saver, the way it fits on the servo, or the servo itself.
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Old 03-07-2017, 01:35 PM   #27
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Originally Posted by theproffesor View Post
Make sure you front C hubs are not on backwards. They are marked with an R and and L. R is right side from the drivers perspective. Also when looking at them from the side with the wheel off, there should be. A reward angle to them. Finallay check to make sure they are the same angle. They make 2, 4, and 6 degree hubs thy fit the 419.

Also make sure the suspension arms are oriented properly and that the shocks are mounted in the same hole. I once bought a used TA-06 Pro and the previous owner had the suspension arms flipped and installed incorrectly.
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Old 03-07-2017, 02:40 PM   #28
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Ok got it fixed, turns out it wanted more toe out on it, which is weird cause when I got it, it had about 1.5 toe out on it, so I must have fixed something in between when I put tow in on it, I always thought toe in stabilized the car on straights, hell I just used toe in on my B44 buggy to make it better on the straights. and that worked on that car, go figure!, well thanks for all your help guys, really appreciate it!
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Old 03-07-2017, 07:57 PM   #29
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Quote:
Originally Posted by niznai View Post
My money sez you have unequal toe on the front

[...]
Quote:
Originally Posted by Slashripper View Post
Ok got it fixed, turns out it wanted more toe out on it, which is weird cause when I got it, it had about 1.5 toe out on it, so I must have fixed something in between when I put tow in on it, I always thought toe in stabilized the car on straights, hell I just used toe in on my B44 buggy to make it better on the straights. and that worked on that car, go figure!, well thanks for all your help guys, really appreciate it!
So it turns out it was a toe problem as suggested in my post above, which means you had not tried everything as you say in your post here:

Quote:
Originally Posted by Slashripper View Post
Tried all your advise, and it still is wandering, on throttle to the right or left, on throttle to the right or left, it does what it wants. and it's not the road I ran my EVO 6 out there and it's fine, even made sure the belts are true and in the middle. Someone please help!!!
Again, without a setup board you will never know if you have equal toe left to right, and more importantly you will never know how much the toe changes on power as opposed to off power.

I think you need to be more systematic in your investigations as well as reading what we are taking the effort to explain.

You don't need to go out and buy an expensive set up system, but you do need a flat surface and some accurate measuring devices (protractor, calliper, etc. things like that). Without these, you are at best going to blunder into a correct setup, but the moment you need to adjust anything again, you'll be back to square one (i.e. relying on another stroke of luck).

To give you some sense of a good setup, your car should go straight as an arrow at all power (throttle) inputs no matter what the terrain is like (within common sense limits). Bumps and pebbles and so on might make the car a bit jittery (you can see the car jerking minutely on the track) but its own setup should pull it straight back on track without you needing to let go the throttle or apply steering corrections. At least that is how my cars go.

And just FYI, my cars rarely have more than 1 deg of toe out (standstill on the bench). Adjusting play and everything else, I bring that to a max of 1.5-2 deg out on coasting (braking). It goes down or even to a hair toe-in on acceleration. This is of course, because I want all the speed I can get and toe-out takes away some of it (keep in mind camber can affect straight line ability as well).

Going around corners will tell you the other side of the story. If your car is barely there in terms of following a straight line, going around a corner will be an exhausting exercise (at speed, of course). Your car will react abruptly and inconsistently so you will need to constantly adjust your steering/throttle input and your car is going to be very inconsistent instead of being very smooth and planted (this is both for your input AND your car's response).

Someone made the point that your servo/servo saver needs attention. That is a very good point I (and everybody else) have overlooked simply because that is the first port of call when you're entering the hobby and we have long forgotten the time when we used crap servos/savers. Very good point.

Good luck
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Last edited by niznai; 03-07-2017 at 09:06 PM.
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